ChromeOS: implement per-user time zone preferences.

chrome/browser/chromeos/system/timezone_util.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_CHROMEOS_SYSTEM_TIMEZONE_UTIL_H_
 #define CHROME_BROWSER_CHROMEOS_SYSTEM_TIMEZONE_UTIL_H_
 
 #include <memory>
 
 #include "base/strings/string16.h"
 
+class Profile;
+
 namespace base {
 class ListValue;
 }
 
 namespace chromeos {
 
 struct TimeZoneResponseData;
 
 namespace system {
 
 // Gets the current timezone's display name.
 base::string16 GetCurrentTimezoneName();
 
 // Creates a list of pairs of each timezone's ID and name.
 std::unique_ptr<base::ListValue> GetTimezoneList();
 
 // Returns true if device is managed and has SystemTimezonePolicy set.
 bool HasSystemTimezonePolicy();
 
 // Apply TimeZone update from TimeZoneProvider.
 void ApplyTimeZone(const TimeZoneResponseData* timezone);
 
+// Returns true if given timezone preference is enterprise-managed.
+// Works for:
+// - prefs::kUserTimezone
+// - prefs::kResolveTimezoneByGeolocation
+bool IsTimezonePrefsManaged(const std::string& pref_name);
+
+// Updates system timezone from user profile data if needed.
+// This is called from chromeos::Preferences after updating profile
+// preferences to apply new value to system time zone.
+void UpdateSystemTimezone(Profile* profile);
+
+// Updates Local State preference prefs::kSigninScreenTimezone AND
+// also immediately sets system timezone (chromeos::system::TimezoneSettings).
+// This is called when there is no user session (i.e. OOBE and signin screen),
+// or when device policies are updated.
+void SetSystemAndSigninScreenTimezone(const std::string& timezone);
+
+// Returns true if per-user timezone preferences are enabled.
+bool PerUserTimezoneEnabled();
+
+// This is called from UI code to apply user-selected time zone.
+void SetTimezoneFromUI(Profile* profile, const std::string& timezone_id);
+
 }  // namespace system
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_SYSTEM_TIMEZONE_UTIL_H_